Validation of the AirGIS exposure modelling at different time scales

This study evaluates the performance of recently redeveloped human exposure modelling system AirGIS for various air pollutants (NOx, NO2 , PM10, and PM2.5) at different time resolutions (monthly, daily, and hourly). Furthermore, strengths and limitations of the model are discussed. Results from the evaluation study suggest that new AirGIS shows satisfying performance in predicting the observed air pollution concentrations at varying time scales and achieved correlation in the range 0.46 – 0.83 (NOx, NO2 ) and 0.40 – 0.61 (PM10, PM2.5). While, the mean bias was found to be in the range 0.1 – 2.5 ppb (NOx, NO2 ) and 0.7 – 4.2 µg/m3 (PM10, PM2.5). These results show that the model is ready for use in both long-term and short-term air pollution exposure assessment over a large geographical area to facilitate health related studies. Although, the evaluation shows satisfying results, further improvements in the new model system are suggested.